(1) Field of the Invention
The present invention generally relates to a hermetic reciprocating compressor used in an air conditioner, a refrigerator, etc. More particularly, it relates to an oil pump for a compressor having an improved construction to reduce the noise produced during operation.
(2) Description of the Prior Art
A conventional compressor includes a housing formed by upper and lower shells 1 and 2 sealing and protecting internal components, a stator 3 installed in upper and lower shells 1 and 2, and provided with power to create a magnetic field, a rotor 5 mounted within stator 3 and rotating by the action of the magnetic field, as shown in FIGS. 1 and 2.
Within rotor 5 is installed a rotation shaft 9 to rotate with rotor 5. A connecting rod 11 is installed at an eccentric part of one end of rotation shaft 9 for converting the rotating motion of rotation shaft 9 into a reciprocating motion. A piston 13 is installed at one end of connecting rod 11 to reciprocate according to the reciprocating motion of connecting rod 11. A cylinder block 15 is provided to the outside of piston 13 to make a space in which a refrigerant is compressed, simultaneously with guiding piston 13. A valve plate 21 with a suction hole 17 and an exhaust hole 19 is mounted on cylinder block 15, and a cylinder head 27 with a suction chamber 23 and an exhaust chamber 25 at one side of valve plate 21.
A gasket 29 is interposed between valve plate 21 and cylinder head 27 for forming a seal, and an oil paddle 30 is provided to an eccentric part 9a of rotation shaft 9 to pump up oil flowing in the bottom of lower shell 2 by centrifugal force generated by the rotation of oil paddle 30. A hole 9b is also formed at eccentric part 9a of rotation shaft 9. Oil paddle 30 has a gap 31 so as to fit into hole 9b, and an oil scattering part 33 is provided to the middle of 11 paddle 30. A push fit portion 35 is formed on the upper part of oil paddle 30, and an oil dipper 36 which is immersed in the oil of lower shell 2 is provided to the lower part of oil paddle 30. Gap 31 is formed to face a centripetal point when rotation shaft 9 turns. Reference numerals 37 and 39 denote a suction muffler sending the refrigerant to cylinder block 15, and a connecting pipe transmitting the refrigerant of suction muffler 37 to cylinder block 15.
Once power is applied to the conventional compressor, a magnetic field is created in the vicinity of stator 3. As rotor 5 rotates by the action of this magnetic field, rotation shaft 9, integrally formed with rotor 5, also rotates, and connecting rod 11 disposed on one end of stator 5 reciprocates rectilinearly, thus making piston 13, provided to the inside of cylinder block 15, reciprocate rectilinearly.
The refrigerant, introduced to suction chamber 23 of cylinder head 27 through suction muffler 37 and connecting tube 39, flows into cylinder block 15 pushing intake valve 31 provided to suction hole 17 of-valve plate 21. Cylinder block 15 becomes compressed as piston 13 is moved, and the refrigerant in cylinder block 15 flows to the outside through exhaust hole 19 of valve plate 21. As push fit portion 35 of oil paddle 30, provided to one eccentric part of rotation shaft 9, rotates in a circle as rotation shaft 9 turns, oil dipper 36 of oil paddle 30 rotates about the center of rotation shaft 9, thus pumping out the oil flowing in lower shell 2 by centrifugal force produced by oil paddle 30.
According to the conventional compressor, push fit portion 35 of oil paddle 30 has directivity, and it must be properly positioned so as to fit into rotation shaft 9 in assemblage. Oil paddle 30 being locked rotates about rotation shaft 9 to pump the oil out, and an abnormal noise is produced by the wave motion of the oil surface, thus increasing the compressor noise.